immature

Silly is a synonym of immature.

As adjectives the difference between immature and silly

is that immature is not fully formed or developed, unripe, not mature while silly is pitiable; deserving of compassion; helpless.

As a noun silly is

a silly person; a fool.

Unversed is a related term of immature.

As adjectives the difference between unversed and immature

is that unversed is inexperienced, untrained while immature is not fully formed or developed, unripe, not mature.

Junior is a related term of immature.

As a noun junior

is junior (especially a junior sportsman).

As an adjective immature is

not fully formed or developed, unripe, not mature.

Untutored is a related term of immature.

As adjectives the difference between untutored and immature

is that untutored is untrained, not taught or educated in a field of knowledge while immature is not fully formed or developed, unripe, not mature.

Immature is a related term of unfinished.

As adjectives the difference between immature and unfinished

is that immature is not fully formed or developed, unripe, not mature while unfinished is not finished, not completed.

Immature is a related term of awkward.

As adjectives the difference between immature and awkward

is that immature is not fully formed or developed, unripe, not mature while awkward is lacking dexterity in the use of the hands, or of instruments.

As an adverb awkward is

(obsolete) in a backwards direction.

As adjectives the difference between amateur and immature

is that amateur is non-professional while immature is not fully formed or developed, unripe, not mature.

As a noun amateur

is a lover {{term|of}} something.

Gullible is a related term of immature.

As adjectives the difference between gullible and immature

is that gullible is easily deceived or duped; , easily cheated or fooled while immature is not fully formed or developed, unripe, not mature.

As adjectives the difference between immature and credulous

is that immature is not fully formed or developed, unripe, not mature while credulous is excessively ready to believe things; gullible.

As adjectives the difference between foolish and immature

is that foolish is lacking good sense or judgement; unwise while immature is not fully formed or developed, unripe, not mature.